From: He Kuang Date: Mon, 13 Apr 2015 11:41:30 +0000 (+0800) Subject: perf probe: Fix segfault when probe with lazy_line to file X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=f19e80c640d58ddfd70f2454ee597f81ba966690;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git perf probe: Fix segfault when probe with lazy_line to file The first argument passed to find_probe_point_lazy() should be CU die, which will be passed to die_walk_lines() when lazy_line matches. Currently, when we probe with lazy_line pattern to file without function name, NULL pointer is passed and causes a segment fault. Can be reproduced as following: $ perf probe -k vmlinux --add='fs/super.c;s->s_count=1;' [ 1958.984658] perf[1020]: segfault at 10 ip 00007fc6e10d8c71 sp 00007ffcbfaaf900 error 4 in libdw-0.161.so[7fc6e10ce000+34000] Segmentation fault After this patch: $ perf probe -k vmlinux --add='fs/super.c;s->s_count=1;' Added new event: probe:_stext (on @fs/super.c) You can now use it in all perf tools, such as: perf record -e probe:_stext -aR sleep 1 Signed-off-by: He Kuang Tested-by: Arnaldo Carvalho de Melo Acked-by: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/1428925290-5623-3-git-send-email-hekuang@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index ff7865ca3ca3..44554c3c2220 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -1066,7 +1066,7 @@ static int debuginfo__find_probes(struct debuginfo *dbg, if (pp->function) ret = find_probe_point_by_func(pf); else if (pp->lazy_line) - ret = find_probe_point_lazy(NULL, pf); + ret = find_probe_point_lazy(&pf->cu_die, pf); else { pf->lno = pp->line; ret = find_probe_point_by_line(pf);